Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
  • C08G69/44—Polyester-amides
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
  • C08G18/4205—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups
  • C08G18/4208—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups containing aromatic groups
  • C08G18/4211—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups containing aromatic groups derived from aromatic dicarboxylic acids and dialcohols
  • C08G18/4216—Polycondensates having carboxylic or carbonic ester groups in the main chain containing cyclic groups containing aromatic groups derived from aromatic dicarboxylic acids and dialcohols from mixtures or combinations of aromatic dicarboxylic acids and aliphatic dicarboxylic acids and dialcohols
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G2110/00—Foam properties
  • C08G2110/0008—Foam properties flexible
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G2110/00—Foam properties
  • C08G2110/0041—Foam properties having specified density
  • C08G2110/0066—≥ 150kg/m3

Definitions

• This invention relates to polyester polyols and especially to co-polyester polyols containing terephthalic acid residues, to their manufacture and to their use in the production of polyurethanes.
• polyester polyols The manufacture of polyurethanes from organic polyisocyanates and polyester polyols is well known.
• the polyesters usually contain from two to three hydroxyl groups per molecule and have molecular weights in the range 1000 to 8000.
• the polyesters are generally made by reacting an aliphatic dicarboxylic acid, especially adipic acid, with an excess, appropriate to the desired molecular weight, of a glycol such as ethylene glycol or diethylene glycol with, where necessary, a higher functionality polyol such as trimethylolpropane or pentaerythritol.
• a glycol such as ethylene glycol or diethylene glycol
• a higher functionality polyol such as trimethylolpropane or pentaerythritol.
• Polyesters of different constitution have been proposed but these have generally failed to achieve commercial importance because of their inability to compete with the adipates on either technical or economic grounds.
• the present invention provides a method for the preparation of a polyester polyol which comprises the steps of :
• the invention also specifically relates to the thus obtained products, which are new copolyesters comprising randomly distributed residues of terephthalic acid and at least one aliphatic dicarboxylic acid and residues of ethylene glycol and possibly one or more further glycols having a molecular weight of not more than 118, whereas the amount of terephthalic acid residues is in the range of l0-60 mole % of the total amount of dicarboxylic acid residues and the amount of ethylene glycol residues is at least l0 % of the total amount of glycol residues.
• any polyethylene terephthalate may be used in step (A) of the method of the invention but it is preferred for economic reasons to use scrap materials such as used photographic film, synthetic fibres or soft drinks bottles and waste from the production of other products made from polyethylene terephthalate.
• Glycols which may be used in step (A) include ethylene glycol, propylene glycol, trimethylene glycol, tetramethy­lene glycol, pentamethylene glycol, hexamethylene glycol, diethylene glycol and mixtures of two or more such glycols.
• ethylene glycol propylene glycol, trimethylene glycol, tetramethy­lene glycol, pentamethylene glycol, hexamethylene glycol, diethylene glycol and mixtures of two or more such glycols.
• at least 1.2 moles of glycol per ethylene terephthalate unit should be used.
• the digestion process is suitably carried out for several hours at 200-270 deg. Celsius under an inert gas such as nitrogen.
• Transesterification catalysts may be used if desired.
• ethylene glycol is used as the digesting glycol
• the product will be a mixture of ethylene glycol and bis hydroxyethyl terephthalate.
• other glycols are used, the product will be a more complex mixture.
• propylene glycol will produce a mixture containing ethylene and propylene glycols, bis hydroxyethyl terephthalate, bis hydroxypropyl terephthalate and hydroxyethyl hydroxypropyl terephthalate.
• Aliphatic dicarboxylic acids which may be used in step (B) of the method of the invention include succinic, glutaric and adipic acids.
• Ester-forming derivatives thereof which may be used include di-lower alkyl esters, especially dimethyl esters. It is particularly convenient to use a commercially available mixture of the dimethyl esters of succinic, glutaric and adipic acids, for example a mixture in the approximate weight ratio of 1:3:1.
• the amount of aliphatic acid or acid derivative used in step (B) will be sufficient to give a polyester polyol product having the desired ratio of terephthalic acid residues to aliphatic acid residues. If necessary to give the desired molecular weight, further glycol can be added at this stage or higher functionality polyols to introduce a degree of branching into the polyester. Suitable higher functionality polyols include glycerol, trimethylolethane, 1,2,6-hexanetriol, trimethylolpropane, pentaerythritol, di-trimethylolpropane, dipentaerythritol, and triglycerides of ricinoleic acid. The hydroxyl functionality of the polyester polyol should preferably not exceed 2.6, the most useful products having functionalities of 2.0 - 2.3.
• Step (B) may be performed under conventional polyesterification conditions, for example temperatures of up to 230 - 240 deg. Celsius with removal of water or lower alkanol.
• the polyester polyols of the invention may be reacted with organic polyisocyanates to form polyurethanes including solid elastomers, microcellular elastomers, coatings, adhesives, thermoplastics and flexible foams.
• the polyisocyanates used will generally depend upon the type of polyurethane being made and may be selected from aromatic polyisocyanates such as diphenylmethane diisocyanate in its various pure, isomer mixture, liquid and unrefined forms, modified isocyanates and tolylene diisocyanate and aliphatic diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate.
• Conventional formulations and techniques may be employed and accordingly, where appropriate, reaction mixtures may contain one or more additives such as catalysts, chain-extenders, blowing agents, surfactants, foam stabilisers, fire-retardants, fillers and pigments.
• polyesters provided by the invention are cheaper than corresponding polyesters made wholly from adipic or other aliphatic dicarboxylic acids and, at the same urethane content, provide higher modulus foams and elastomers.
• Useful microcellular shoe soles were obtained by reacting Product X with diphenylmethane diisocyanate in a conventional formulation.
• the final product, PRODUCT Y had the following analysis : Hydroxyl value 44.6 mg KOH/g, acid value 0.08 mg KOH/g, Methoxyl content 0.13 % (as methanol) and viscosity at 100 deg. Celsius, 550 centistokes.
• Useful microcellular shoe soles were obtained by reacting Product Y with diphenylmethane diisocyanate in a conventional formulation.
• DIGESTION PRODUCT C 3195 parts by weight DIGESTION PRODUCT C were reacted as in Example 3 with 2657 parts by weight of a commercial mixture of dimethyl esters of adipic, glutaric and succinic acids (in an approximate weight ratio of 1:3:1) and 12.8 parts by weight of trimethylol propane together with 0.3 parts by weight of tetrabutyl-o-titanate catalyst. 1235 parts by volume of methanol were recovered over 9 hours from 190 Deg. C to 230 Deg. C. After a further 10 hours at 230 Deg. C the product had the following analysis :
• microcellular elastomer samples were prepared on an ELASTOGRAN EMB machine (VTE-machine), using conventional operating conditions :

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Polyurethanes Or Polyureas (AREA)
• Polyesters Or Polycarbonates (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10598699

Family Applications (1)

Country Status (10)

Cited By (10)

Families Citing this family (3)

Citations (1)

• 1986
  • 1986-05-30 GB GB868613199A patent/GB8613199D0/en active Pending
• 1987
  • 1987-05-12 ZA ZA873394A patent/ZA873394B/xx unknown
  • 1987-05-13 IL IL82506A patent/IL82506A0/xx unknown
  • 1987-05-18 GB GB878711681A patent/GB8711681D0/en active Pending
  • 1987-05-21 YU YU00913/87A patent/YU91387A/xx unknown
  • 1987-05-21 KR KR870005023A patent/KR870011171A/ko not_active Application Discontinuation
  • 1987-05-21 EP EP87304544A patent/EP0248570A1/fr not_active Withdrawn
  • 1987-05-22 AU AU73321/87A patent/AU7332187A/en not_active Abandoned
  • 1987-05-27 DK DK272487A patent/DK272487A/da not_active Application Discontinuation
  • 1987-05-29 HU HU872472A patent/HUT44050A/hu unknown
  • 1987-05-30 JP JP62137583A patent/JPS62290723A/ja active Pending

Patent Citations (1)

Non-Patent Citations (1)

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